Corrosion resistant body lining and seat for butterfly valve

ABSTRACT

A butterfly valve wherein all of the surfaces of the valve body which are exposed to the fluid being controlled by the valve is covered with a one piece corrosion-resistant lining. The valve also includes a corrosion-resistant seat which is supported and retained by the lining.

United States Patent Paul E. Fitting Camp Hill, Pa.

Nov. 14, 1968 Mar. 9, 1971 Allis-Chalmers Manufacturing CompanyMilwaukee, Wis.

inventor Appl. No. Filed Patented Assignee CORROSION RESISTANT BODYLININ G AND SEAT non BUTTERFLY VALVE 2 Claims, 2 Drawing Figs.

U.S.Cl I 137/375, 251/306 1m. Cl. ..Fl6k 27/12, F16k 1/226 FieldofSearch 137/375;

[56] References Cited UNITED STATES PATENTS 2,863,630 12/1958 Broz251/173 3,100,500 8/1963 Stillwagon 251/306X 3,241,806 3/1966 Snell251/306X 3,306,573 2/1967 Tretil 251/306 3,425,439 2/1969 Duffey et a1.137/375 Primary Examiner-Henry T. Klinksiek AttorneysJohn P. Hines,Robert B. Benson and Thomas F.

Kirby ABSTRACT: A butterfly valve wherein all of the surfaces of thevalve body which are exposed to the fluid being controlled by the valveis covered with a one piece corrosion-resistant lining. The valve alsoincludes a corrosion-resistant seat which is supported and retained bythe lining.

' CORROSION RESISTANT BODY LINING AND SEAT FOR BUTTERFLY VALVE Thisinvention pertains in general to butterfly valves and more particularlyto a butterfly valve wherein the metallic surfaces of the valve body arecompletely covered by a noncorrosive lining and wherein acorrosion-resistant seat is supported and retained by thecorrosion-resistant lining.

Because of their comparative low cost and simplicity of design,butterfly valves are being utilized in more and varied applications. Inmany applications butterfly valves are utilized to control the flow ofwater and other corrosive fluids. Unless adequate protection is providedfor the flow passages of the valve, corrosive effect, a buildup ofcorrosive products and deposition of foreign materials may materiallyshorten the usein] life of the valve. This action of the fluid can beovercome by fabricating the valve of a corrosion-resistant material suchas stainless steel. This, however, adds considerably to the cost of thevalve and in large installations may prove to be prohibitivelyexpensive.

Another approach for a solution to the problem is to line the portionsof the valve which are exposed to the fluid with a noncorrosivesubstance such as rubber. This, however, presents two problems: one,being. that it is extremely difficult to protect from the fluid thoseportions of the body which are not lined; and, secondly, it prohibitsthe use of a metallic seat which is necessary in some applications wherepositive sealing is required.

It is, therefore, the general object and intention of this invention toprovide a butterfly valve with a seat of noncorrosive material and witha noncorrosive lining on all of the surfaces I of the valve body whichare exposed to the fluid being controlled and which lining supports andretains the valve seat in the valve body.

This and other objects of the subject invention will become more fullyapparent as the following description is read in light of the attacheddrawing wherein:

FIG. 1 is a side view of one form of butterfly valve constructed inaccordance with the invention; and I FIG. 2 is a cross section takenalong the lines Il-Il of FIG. 1.

Referring to the attached drawing, the butterfly valve body of thesubject invention is generally designated 6. To provide sufficientstrength to the valve body, the outer portion 7 is metallic such as forinstance cast iron. The valve body is provided with a pair of oppositelydisposed shaft housings 8, and also with a fluid confining passageway 9extending through the body. Each of the shaft housings 8 is providedwith a shaft bore 11 to receive a butterfly valve shaft (not shown).

In most instances the metallic body portion 7 is made of materials whichare subject to corrosion. It would be possible to construct this portionof the valve of a noncorrosive steel such as for instance stainlesssteel; however, this would increase the price of the valve to the extentthat it would be prohibitively expensive for many applications.Therefore, in applications where water or other corrosive fluids arebeing controlled; it is necessary to isolate the metallic portions ofthevalve body which are susceptible to corrosion. To this end, a one piecelining 12 of corrosion-resistant material is applied about the interiorsurfaces of the valve body. This lining 12 is preferably molded andbonded to the interior of the valve body. It should be understood thatthe precise manner of molding the lining to the valve body does not forma part of this invention, and it is quite possible that the lining couldbe mechanically attached to the valve body. The lining l2 completelycovers the interior surface of the passageway 9 as well as the exposedinterior surfaces of the bores 11. Furthermore, the lining 12 extends tothe ends of the passageway 9 and radially outward therefrom to form anannular lip 13 at either end of the passageway.

A metallic seat ring 14 preferably constructed of stainless steel or anyother similar noncorrosive metal may be applied about the passageway 9.This metallic seat ring 14 may be completely supported and retained bythe linin 12.

Relieved portions 16 may be provided at t e ends of the shaft housing 8to pemrit use of thrust bearing or a shaft packing.

From the description it can be seen that the surfaces of the valve bodywhich might possibly .be exposed to the fluid are completely lined witha one piece lining of noncorrosive material thereby adequately isolatingthe metallic portion of the valve body from the fluid. Furthermore, theseat ring 14 may be also supported and retained in the valve body. Sincethe seat ring is composed of a noncorrosive material such as stainlesssteel, it is not afi'ected by the corrosive action of the fluid andfurthermore, since it is insulated from the less noble metal of thevalve body, galvanic action between the valve seat ring and the valvebody is prohibited.

Although only one embodiment of the subject invention has been hereinshown and described, other embodiments will be apparent to those skilledin the art after they have read this description and it is intended thatall such embodiments as come within a reasonable interpretation of theappended claims be covered.

I claim:

1. In a butterfly valve having a metallic body with a fluid passagewaytherethrough and a pair of oppositely disposed shaft bores, theimprovement comprising: a one piece lining of corrosion-resistantmaterial applied about the interior surface of said body which definessaid passageway and said shaft bores; and a corrosion-resistant seatring supported and retained exclusively by said lining free of anycontact with said valve body, said seat ring supported and retainedexclusively by said lining free of any contact with said valve body,said seat ring positioned about said fluid passageway to one side of theaxis of said shaft bores for fluid sealing engagement to effectivelyseal said passageway when the valve is in the closed position.

2. In a butterfly valve having a metallic body with a fluid passagewaytherethrough and a pair of oppositely disposed shaft bores, theimprovement comprising: a one piece lining of corrosion-resistantmaterial applied about the interior surface of said body which definessaid passageway and said shaft bores; and a metallic seat ring composedof a metal more resistant to corrosion than the metal of said valve bodypositioned about said fluid passageway for fluid sealing engagement toeffectively seal said passageway when the valve is in the closedposition.

3.33 UNITED s'rxvncs 'IA'II'JNI. OFFICE CERTH ICATE OF CORRECTIGN PatentNo. 3,568,709 Dated March 9, 1971 Invcntor(s) Paul E. Fitting It iscertified that error appears in the above-Mentified patent and that saidLetters Patent are hereby corrected as shown below:

r- Column 2, linee H4, H5, 16, cancel beginning with "supported andretained exclusively by said lining free of any contact with said valvebody, said seat ring".

Signed and sealed this 6th day of July 1971.

(SEAL) Attest:

. EDWARD M.FLETGHER,JR. WILLIAM E. SCHUYLER, JR

Attesting Officer Commissioner of Patents

1. In a butterfly valve having a metallic body with a fluid passagewaytherethrough and a pair of oppositely disposed shaft bores, theimprovement comprising: a one piece lining of corrosion-resistantmaterial applied about the interior surface of said body which definessaid passageway and said shaft bores; and a corrosion-resistant seatring supported and retained exclusively by said lining free of anycontact with said valve body, said seat ring supported and retainedexclusively by said lining free of any contact with said valve body,said seat ring positioned about said fluid passageway to one side of theaxis of said shaft bores for fluid sealing engagement to effectivelyseal said passageway when the valve is in the closed position.
 2. In abutterfly valve having a metallic body with a fluid passagewaytherethrough and a pair of oppositely disposed shaft bores, theimprovement comprising: a one piece lining of corrosion-resistantmaterial applied about the interior surface of said body which definessaid passageway and said shaft bores; and a metallic seat ring composedof a metal more resistant to corrosion than the metal of said valve bodypositioned about said fluid passageway for fluid sealing engagement toeffectively seal said passageway when the valve is in the closedposition.